Which of the following statements is correct for a system with gain margin close to unity or a phase margin close to zero?
(a) The system is relatively stable
(b) The system is highly stable
(c) The system is highly oscillatory
(d) None of the above
Answer: The system is highly oscillatory
More MCQs and Answers Control System
1. In an open loop control system
2. For open control system which of the following statements is incorrect?
3. A control system in which the control action is somehow dependent on the output is known as
4. In closed loop control system, with positive value of feedback gain the overall gain of the system will
5. Which of the following is an open loop control system?
6. Which of the following statements is not necessarily correct for open control system ?
7. In open loop system
8. Has tendency to oscillate.
9. A good control system has all the following features except
10. A car is raining at a constant speed of 50 km/h, which of the following is the feedback element for the driver?
11. The initial response when the output is not equal to input is called
12. A control system working under unknown random actions is called
13. An automatic toaster is a ______ loop control system.
14. Any externally introduced signal affecting the controlled output is called a
15. A closed loop system is distinguished from open loop system by which of the following?
16 Is a part of the human temperature control system.
17. By which of the following the control action is determined when a man walks along a path?
18. Is a closed loop system.
19. Which of the following devices are commonly used as error detectors in instruments?
20. Which of the following should be done to make an unstable system stable?
21. Increases the steady state accuracy.
22. A.C. servomotor resembles
23. As a result of introduction of negative feedback which of the following will not decrease?
24. Regenerative feedback implies feedback with
25. The output of a feedback control system must be a function of
26. Is an open loop control system.
27. A control system with excessive noise, is likely to suffer from
28. Zero initial condition for a system means
29. Transfer function of a system is used to calculate which of the following?
30. The band width, in a feedback amplifier.
31. On which of the following factors does the sensitivity of a closed loop system to gain changes and load disturbances depend?
32. The transient response, with feedback system
33. The second derivative input signals modify which of the following?
34. Which of the following statements is correct for any closed loop system?
35. Which of the following statements is correct for a system with gain margin close to unity or a phase margin close to zero?
36. Due to which of the following reasons excessive bond width in control systems should be avoided?
37. In a stable control system backlash can cause which of the following?
38. In an automatic control system which of the following elements is not used?
39. In a control system the output of the controller is given to
40. A controller, essentially, is a
41. Which of the following is the input to a controller?
42. The on-off controller is a _____ system.
43. The capacitance, in force-current analogy, is analogous to
44. The temperature, under thermal and electrical system analogy, is considered analogous to
45. In electrical-pneumatic system analogy the current is considered analogous to
46. In liquid level and electrical system analogy, voltage is considered analogous to
47. The viscous friction co-efficient, in force-voltage analogy, is analogous to
48. In force-voltage analogy, velocity is analogous to
49. In thermal-electrical analogy charge is considered analogous to
50. Mass, in force-voltage analogy, is analogous to
51. The transient response of a system is mainly due to
52. Signal will become zero when the feedback signal and reference signs are equal.
53. A signal other than the reference input that tends to affect the value of controlled variable is known as
54. The transfer function is applicable to which of the following?
55. From which of the following transfer function can be obtained?
56. Is the reference input minus the primary feedback.
57. The term backlash is associated with
58. With feedback _____ increases.
59. By which of the following the system response can be tested better?
60. In a system zero initial condition means that
61. In a system low friction co-efficient facilitates
62. Hydraulic torque transmission system is analog of
63. Spring constant in force-voltage analogy is analogous to
64. The frequency and time domain are related through which of the following?
65. An increase in gain, in most systems, leads to
66. Static error coefficients are used as a measure of the effectiveness of closed loop systems for
specified ________ input signal.
67. A conditionally stable system exhibits poor stability at
68. The type 0 system has ______ at the origin.
69. The type 1 system has ______ at the origin.
70. The type 2 system has ______ at the origin.
71. The position and velocity errors of a type-2 system are
72. Velocity error constant of a system is measured when the input to the system is unit _______ function.
73. In case of type-1 system steady state acceleration is
74. If a step function is applied to the input of a system and the output remains below a certain level for all the time, the system is
75. Which of the following is the best method for determining the stability and transient response?
76. Phase margin of a system is used to specify which of the following?
77. Addition of zeros in transfer function causes which of the following?
78. Technique is not applicable to nonlinear system?
79. In order to increase the damping of a badly underdamped system which of following compensators may be used?
80. The phase lag produced by transportation relays
81. In a stable control system saturation can cause which of the following?
82. Which of the following can be measured by the use of a tachogenerator?
83. Is not a final control element
84. Which of the following is the definition of proportional band of a controller?
85. In pneumatic control systems the control valve used as final control element converts
86. Pressure error can be measured by which of the following?
87. Which of the following devices is used for conversion of co-ordinates?
88. The effect of error damping is to
89. Technique gives quick transient and stability response
90. A phase lag lead network introduces in the output
91. Which of the following is the non-linearity caused by servomotor?
92. Can be extended to systems which are time-varying?
93. When the initial conditions of a system are specified to be zero it implies that the system is
94. Which of the following is an electromagnetically device?
95. A differentiator is usually not a part of a control system because it
96. If the gain of the critical damped system is increased it will behave as
97. In a control system integral error compensation _______ steady state error
98. With feed back _____ reduces.
99. An amplidyne can give which of the following characteristics?
100. Which of the following can be measured by LVDT?
101. Directly converts temperature into voltage.
102. The transfer function technique is considered as inadequate under which of the following conditions?
103. Which of the following is the output of a thermocouple?
104. A.C. servomotor is basically a
105. The first order control system, which is well designed, has a
106. Which of the following is exhibited by Root-locus-diagrams?